CAMAC-based data acquisition for the Apnea Unit

Summary form only given. The Apnea Unit, an active-passive neutron examination and assay unit, extends the traditional differential dieaway technique for the nondestructive assay of transuranic waste. A key aspect of the new capabilities of this device is the novel approach to the data acquisition. The unit currently gives individual support to over 80 ³He gas proportional tubes for neutron detection and maintains a detailed list-mode time history for each detector. The CAMAC-based data acquisition system centers on a multi-time tagging module which records detector hits and their associated time. The data are managed in a CAMAC crate by an event handler which services the time tagging modules and blocks the resulting data through a FIFO into a personal computer. The richness of the resulting data is already being used to profile the contents of an assay drum and to differentiate events associated with cosmic rays